Two-cycle motor



' TWO-CYCLE MOTOR Filed Nov. 23, 1927 Patented Feb. 4, 1930 y y l( c UNITED sTATEs PATENT OFFICE HERBERT J. KRATZER, F ST. LOUIS, MISSOURI TWO-CYCLE MOTOR Application led November 23, 1927. Serial No.. 235,203.

This invention relates to improvements in take and compression kportions of piston a two-cycle internal combustion motor having stroke. l v for its primaryobject the purpose of provid- Referring by numerals to the accompanying improved means wherebyamaximum fuel ing drawings, 1 designates the cylinder of eiliciency will be obtained with the simplest this improved two-cycle motor having the 50 and most reliable mechanical means. cylinder head 3 and depending from the 'A further object of the invention is to cylinder is the upper portion` 4 of the crank provide a motor with' means which will enhousing 5 and secured to the housing is the tirely change the true operative cycle as compan on. l" pared to either of the four-cycle or two-cycle Horizontally disposed and supported with- 55 principle now in use. v inthe housing 5 is a crankshaft 6 having a A further object of the invention is in crank 7 and secured to said crankis a con-` providing the motor with means whereby in necting rod 8, said rod being secured at its the cycle of operation the expansion or workupper end to the wrist pin 9 of a piston 10.v 5 ing stroke is longer than the compression Mounted in the cylinder 1 is a sleeve 11, said 60 stroke. V sleeve bearing against the cylinder wall and Another further object of the invention is the piston 10 being mounted within the sleeve. in providing the motor withimproved means Abutting against the cylinder 1 on one side whereby the exhaust port is closed before the is an intake manifold 12 and leading up- 2 inlet port is closed. f wardly from said manifold to the cylinder l 65 Still another object of the invention is in is an intake port 13 and for communication providing a two-cycle internal combustion with said port is an upwardly and inwardly motor of a construction whereby the power, inclining opening 14 which is formed in the t cycle operation of the motor is given an exsleeve 11. Located in abutting relation with' 5 pansion ratiowhicli exceeds the compressionl the opposite side of the cylinder l is an eX- 70 ratio. haust manifold 15 and formed inthe cylin- Another still further object of the invender wall is a port 16 which forms communition is to provide a two-cycle motor with imcation between the cylinder 1 and the eX- proved means for introducing the 4fuel haast m'anlfol'd 15 and for operative oo mcharges into the cylinders in a different munlcltlol Wth Sal@ POI 16 1S aIlOPelllllg manner. 17 which is formed in the sleeve 11.

Other and further objects will appear in Formed 0nthe crmkshaft 6 1S a CMP 18 the specification and be specifically pointed ang mountd over Sallcall 1S an 'Ccentnfg out in the appended claims, reference being an extending upwar y rom Sald accentue Y is an extension 20 and pivotally secured at 21` had in the acompimymg dlawmgs exem' to said extension 20 is a leg 22 which is deplifying the invention, and in which l. v Y pended from the sleeve 11. F iguie lis avertical sectionvtalien through FOrr the purpose of illustration only one l thsimplfoved motor on the approximate une cylinder of this improved two-cycle motor 40' ,indicated-at L-I in Fig 2 is 'shown although in practise the motor will 85 Figure 2 iS hOllOIltal SGCOD @ken @P- comprise several cylinders and operable parts proximately on the 11n@ II-II 0f F 1g. 11 l therefor and itis my intention to provide a Figure 3 is a schematic diagram indicating gaseous pressure 'by means removed from the approximate time and duration 0f cyclic ycrankcaseiof the motor and to maintainl a piston operations of expansion, exhaust, inpressure in the intake manifold 12 as shown andl illustrated in m pending application, Serial No. 164,898, led January 31, 1927, this application showing a tubular eontrollin member 23 mounted in the intake manifol 12 and having an opening 24 formed therein for communication with the port 13.`

In the operation of this improved motor, when a gaseous pressure'is maintained with in the controlling member 23 which is located inside of the intake manifold 12, and the motor is in operation in'which the crankshaft 6 will be rotated in the direction of the arrow 25 in Fig. 1 in which the piston-10 is being travelled downwardly by force of the explosion created in the chamber 26 which is provided by the sleeve 11, the openings 14 and 17 of the sleeve 11 will be in positions upwardly disposed above respective ports 13 and 16.- As the piston travels during the first 80 degrees of crank rotation with increasing ve-- sleeve 11 has startedon its downward stroke and thereby the exhaust opening 17 will begin to communicate with the exhaust port 16 of the vexhaust -manifold 15. Assuming constant angular velocity of crankshaft, it

- can be seen during the next and last degrees of crank rotationv necessary to complete thecdownward stroke of the piston, the

pistonwill travel at decreasing speed the remaining approximate six per cent of its stroke at a speed relatively slow to a total stopat 180 degrees. As the eccentric 19 whiehoperates the sleeve 11 is delayed or located 80 degrees behind the crank throw, said eccentric will approach and pass its highest speed of travel during the time of the shortest angular travel of the crank shaft.

After the piston has reached the end of its power cycle stroke vafter 180 degrees of crank throw and the piston is being travelled upwardly on its compression stroke or cycle, it is obvious therefore that the exhaust open ing 17 of the sleeve is in approximate full register with the exhaust port 16, this occurring when the crank throw is approximately 80 degrees past the dead center, and as said piston is now travelling upwardly and with increasing velocity compared to the constant angular velocity of the crankshaft, the piston begins to pass the exhaust opening 17 which is in register Ior alinement with the exhaust port 16, therefore the closing'oper* ation of the'exhaust opening 17 is even more prompt than the Opening operation: with respect to the opening 17 communicating with the exhaust port 16. I

. At labout the time the piston reached the end of its downward stroke,n the downward travel of the sleeve 11 caused the intake opening 14 to commence communication with A the inlet port 13 and by reason of the upward swirling of the fuel forcing the burnt gases in the cylinder co're downwardly where they will be discharged through the exhaust opening 17 and exhaust port 16, this occurring before the opening 17 is closed by the piston.

As the opening 17 is being closed by the upward travel of the piston, the inlet opening 14 has just travelled to full opening register with the inlet port 13 and immediately after the exhaust opening 17- has been closed the piston will begin to close the inlet opening 14, said opening 14 however not being entirely closed until after the exhaust opening 17 has been sealed or closed by the piston. Immediately upon the closing of the inlet opening 14 the compression operation of'the piston begins and is continued until the piston reaches the end of its upward stroke and immediately thereafter the piston is vforced downwardly on its'power stroke or cycle and before the piston on its downward travel passes respective openings 14 and 17 in the sleeve 11, the said openings are out of register with respective inlet and outlet ports 13 and 16, said ports then being sealed by the sleeve body.

Briefly summarized, the intake opening 14 starts to register with intake port 18 to admit fuel to the cylinder when the crankshaft is at lower dead center, the size of intake opening increasing at a decreasing rate of speed until wide open at the time the crank is 80 degrees past lower dead center, the inlet vopenin 14 then being rapidly closed during f the fo lowing 10 degrees of crank rotation' by piston travelling at increasing velocity. During the time the crank revolved through approximately 90 degrees starting y from low er dead center, the piston actuated by the crank and connecting rod inthis distance of its travel is truly an exhaust stroke as the piston during the greater portion of this part of the upward stroke displaces the spent gases below'j' the exhaust port level out ilo through the exhaust together with the spent gases being displaced from the upper end of the cylinder by the upwardly directed tangential stream of new fuelcharge.

A roller 28 is mounted on the pin 21 for operative engagement with the guideway 29 in the housing 5.

Vith reference to Fig. 3-which is intended to show the cyclic operations accomplished by the piston, the curve portion starting from A and extending to B representing the travel of crank .wrist pin during expansion or'working stroke of piston.

duration of crank pin travel during which time exhaust port is open followed by curve C D representino` crank pin position during irst portion of C D thus graphically showing intake port remaining open after exhaust port is closed with compressionas indicated starting before intake ports are actuallyl closed. This feature of intake lclosing after exhaust port closes, coupled with the fact that pressure in intake manifold `is the primary cause of displacing the spent gases in cylin- Ader through exhaust port constitutes the desirable operating characteristicv of inherently producing higher compression pressure with increase of. engine speed. The portion of travel from C to F on curve which represents the time intake valve remains open after exhaust port closes at the beginning of the compression portion of stroke is included in the compression stroke by virtue of the increased pressure in the intake manifold producing a pressure in cylinder above piston at time crank arrives at point -F which 'pressure would ,be greater than had piston moved due.

to crank travel from ports closed. I f

Obviousl but one specific showing of the invention is disclosed in which the sleeve travel is delayed behind the piston travel and the downward travel of said sleeve controls the instant of opening both inlet and exhaust ports; the piston travel on upward curve C to F with all 'strokes determining the instant of closing respective ports. However, it is anticipated v that the ports can be located in different positions with respect to .other eccentric positions relative tothe crank, one of which other positions of eccentric location in respect to` crank throw being approximately Sl() de ees in advance in which the 'sleeve travelupwardly would determine the instant ofmpening of exhaust and inlet ports and also the closing of inlet port and the piston on vits upward stroke determining the instant of closing the exhaust port4 only. With this in view it is clear that other modifications than that shown can be made within the scope of the invention. f

What I claim is: v, y

1. A two-cycle motor having a cylinder, an inlet port and an outlet port, a sleeve having openings therein which are cooperable with respective ports, a piston reciprocal' within saidsleeve being cooperable with the open# ings of said sleeve for closing them onuits out ward stroke, a crankshaft, and a connecting Curve from v B to C indicates approximate timing and rod for said sleeve and said piston operable fromsaid shaft.

2. A `two-cycle motor having a c linder, an exhaust port and an inlet port or said cylinder, a sleeve cooperable with said ports, a piston mounted in said sleeve, means provided in the sleeve whereby the exhaust port is closed before the inlet port is closed by the piston, a connecting rod for said sleeve and said piston, and a crank shaft to which Said connect-ing rods are directly connected.

- 3. A t-wo-cycle motor having a cylinder, an inlet port and an exhaust port for said cylinder, a sleeve cooperable with said ports, and a propelling piston cooperable with said ports, said ports being disposedv a distance away from theA iston when the piston is at the end of its wor ing stroke.

4. A two-cycle motor having a cylinder, an inlet port and an exhaust port for said cylinder, a sleeve cooperable with said ports, a propelling piston' reciprocal in said sleeve,

`said portsgbeing disposed in the cylinder intermediate of the working length of the cylinder, and alcrank shaft with which said sleeve and said piston are cooperably connected. y 5. A two-cycle motor having a cylinder, an inlet andan exhaust port in said cylinder, a reciprocatory sleeve cooperable with said ports when said sleeve is inwardly travelled, a piston cooperable with said ports when said pistonis outwardly travelled, and a crank shaft with which said sleeve and said piston are cooperably connected. I

v 6. A two-cycle motor having-a cylinder, an inlet port and an outlet port, a sleeve having openings therein which are cooperable with respective ports when said sleeve is inwardly travelled, a piston cooperable with said\open ings of said sleeve when said piston is outwardly travelled, and a crankshaft with which said ,sleeve and said piston are cooperably connected.

7. A two-cycle motor having a cylinder, an

upwardl inclining inletrport in communicae tion wit said cylinder, said port being directed in saidv cylinder tangentially'thereto, and an exhaust port leading from said cylinder on a plane below said inlet port and above the piston whenthe piston is at the end of its wor 'ng stroke.

8.- A two-cycle motor having a cylinder, an exhaust port, an inlet port disposed on a plane above the exhaust port, a sleeve cooperable l with said ports, and a single piston in said sleeve, said piston and said sleeve providing means whereby the piston closes the inlet after the exhaust port.

9. A two-cycle motor having a cylinder, an inlet port and anexhaust port for said cylinder, said inlet port beingl .disposed on a plane above the exhaust port, ya sleeve cooperable` with said pdrts, and a piston, said ports being port disposeda'vt'listance away from the piston '1 when the piston is at the end of its working stroke, and a crank shaft to which said sleeve and said piston are cooperably connected.

10. A two-cycle motor having a cylinder, an inlet port and an exhaust port for saidcylinder, said inlet port being disposed on a plane above the exhaust port, a sleeve cooperable with said ports, and a piston reciprocal in said sleeve, said ports being disposed in the cylinder remote from the cylinder head thereof and from the piston when the piston is at the end of its working stroke.

11. A two-cycle motor having a cylinder, an inlet port and an exhaust port forA said cylinder disposed intermediate of the length thereof, said inlet port being disposed on va plane above the exhaust port, a sleeve in said cylinder 'having ports for cooperation with said cylinder ports, a piston in said sleeve, said ports of said sleeve being disposed a distance away from the piston when the piston is at the end of its working stroke.

12. A two-cycle motor having a cylinder, an intake manifold, an inlet port forming means of communication from said manifold to said cylinder, means for maintaining a pressure above atmospheric on the gaseous fuel contained in said manifold, an exhaust port, a reciprocatory sleeve cooperable with said inlet port and said exhaust port when said sleeve is inwardly travelled, a piston col operable with both of said ports when said piston is outwardly travelled, a crankshaft, and operating means for said sleeve and said piston directly connected to said shaft.

13. A two-cycle motor having a ported cylinder, a ported sleeve in said cylinder, a piston in said sleeve, means for reciprocating said sleeve and said piston, the ports of said sleeve being disposed in positions in said sleeve whereby the approximate length of the inward stroke of the piston will be an expanding power stroke, and the said ports of said sleeve being adapted to` communicate with the ports of the cylinder during the outward stroke of the piston in a manner wherein the first part of the outward stroke of the iston will provide for the exhausting and re ueling operations of the cylinder, and the latter,` part of the outward stroke of ythe piston. will be a compression stroke.

14. A two-cycle motor having a ported cylinder, a ported sleeve in said-cylinder, a.

piston in said sleeve, means for reciprocating said sleeve and said piston, the ports of said sleeve being disposed in positions in said sleeve whereby the approximate length of the inward stroke of the piston will be an expanding power lstroke while the cylinder ports are closed, and the said ports .of said sleeve bein adapted to communicate with the ports o the cylinder during the outwardstroke of the. piston in a manner wherein the first part of the outward stroke of the piston will provide for the exhausting and refueling operations of the cylinder, and the latter party of the outward stroke of the piston will be a compression stroke during when all of said ports are closed.

y 15. A two-cycle motor having a ported cylinder, a ported sleeve in said cylinder, a. piston in said sleeve, means for reciprocating said sleeve and said piston, the ports of said sleeve being disposed in positions in said sleeve whereby the approximate length of the inward stroke of the `piston will be an expanding power stroke while the cylinder ports are closed, and the 'said ports of said sleeve being adapted to communicate with the ports of the cylinder during the outward stroke of the piston in a manner wherein the first part of the outward stroke of the piston will provide for the exhausting and refueling operation of the cylinder, and the latter partf of the outward stroke of the piston will be a compression stroke during when all of said ports are closed b the piston. y

, 16. A two-cyc e motor having a ported cylinder, a sleeve in said cylinder having an inlet port and an exhaust port formed in the wall thereof intermediate of the length of the sleeve, the inlet port of said sleeve being disposed on a plane above the exhaust port, -a piston in said sleeve, means for reciprocatinfr said sleeve and said piston, said ports of said sleeve adapted to intermittently communicate with respective ports of said cylinder when said sleeve is reciprocated, said ports of said sleeve being out of communication with the ports of the cylinder during the approximate length of inward travel of the piston and adapted to communicate with the cylinder ports during the approximate first part of the outward travel of the piston.

17. An internal combustion motor having a' cylinder, an upwardly inclined inlet port in communication with said cylinder, said port being directed in said cylinder tangentially thereto, an exhaust port leading from said cylinder on a plane inwardly of said inlet port and above the piston when the piston is at the end of its working stroke, and a sleeve cooperable with said ports.

18. An internal combustion motor having a cylinder, an upwardly inclining inlet port adapted to communicate with said cylinder, a sleeve in said cylinder having an opening therein for communication with said inlet port, said inlet port and said opening of said sleeve being directed in said cylinder tangentially thereto, and an exhaust port leading ports of said sleeve being adapted to communicate with the ports of the cylinder during the outward stroke of the piston in a manner wherein the first part of the outward stroke of the piston will provide for the exhausting and refueling operations of the cylinder, and the latter part of the outward stroke of the piston will be a com ression -stroke which is shorter in length t an the approximate length of the expansion stroke of the piston.

HERBERT J. KRATZER. 

